JP4358825B2 - Fuel cell power generation system - Google Patents

Description

  The present invention relates to a power generation apparatus (system) and an operation method thereof, and more particularly, to a fuel cell power generation system that generates power using a fuel cell and an operation method thereof.

  Conventionally, a fuel cell power generation system capable of high-efficiency small-scale power generation is easy to construct a system for using thermal energy generated during power generation and can realize high energy use efficiency. Is preferably used.

  The fuel cell power generation system includes a fuel cell as a main body of the power generation unit. As this fuel cell, for example, a polymer electrolyte fuel cell, a phosphoric acid fuel cell, or the like is generally used. In these fuel cells, power generation is performed using hydrogen-rich gas (hereinafter referred to as fuel gas) rich in hydrogen and air (hereinafter referred to as oxidant gas). Therefore, the fuel cell system is provided with a fuel processor for generating fuel gas necessary for power generation. In this fuel processor, natural gas or the like supplied from a supply means such as natural gas is converted into hydrogen gas by a steam reforming reaction, thereby generating a fuel gas rich in hydrogen. At this time, the reaction space where the steam reforming reaction is performed in the fuel processor is heated and kept at a predetermined temperature by, for example, heat obtained by burning natural gas.

  By the way, in the operation of a conventional power generation system including a fuel cell power generation system, in order to prevent wasteful consumption of fuel gas or the like used for power generation, a power load (hereinafter simply referred to as an electronic device or the like) connected to the power generation system. It is preferable that the supply amount of the fuel gas or the like to the fuel cell or the like is appropriately controlled according to the power consumption of the power load). In other words, in the fuel cell power generation system, in order to prevent wasteful consumption of natural gas or the like used to generate fuel gas, supply of natural gas or the like to the fuel reformer according to the power consumption of the power load The amount is preferably controlled as appropriate.

  Therefore, the power generated by the power load connected to the power generation system is supplied in combination with the power generated by the power generation and the commercial power, and the power generation is stopped during the time when the power consumption of the power load is low. A power generation system that supplies only commercial power has been proposed (see, for example, Patent Document 1).

  Further, when the power consumption of the power load is equal to or greater than a predetermined threshold, the output power is controlled to follow the fluctuation of the power consumption of the power load detected by the load power detection means, and the power consumption of the power load is predetermined. A power generation system that stops the power generation operation when the value is equal to or less than the threshold value is proposed (see, for example, Patent Document 2).

  According to these proposals, since the consumption of raw materials necessary for power generation such as natural gas is appropriately controlled according to the power consumption of the power load, it is possible to construct a suitable power generation system with higher energy utilization efficiency. It becomes possible.

  Hereinafter, a conventional fuel cell power generation system will be described as an example, and its configuration and operation pattern will be described with reference to the drawings.

  FIG. 6 is a block diagram schematically showing a configuration of a conventional fuel cell power generation system.

  As shown in FIG. 6, a conventional fuel cell power generation system 100 controls a fuel cell 100a that generates power using a fuel gas and an oxidant gas, the output power of the fuel cell 100a, and the power generation of the fuel cell 100a. By detecting the power consumption of the power load 100e, which will be described later, an output control means 100b for controlling start and stop of operation and a control signal necessary for the output control means 100b to control the output power of the fuel cell 100a, etc. It has load power detection means 100c for outputting and a storage battery 100d for storing excess output power. Here, the storage battery 100d is electrically connected at the connection between the output control means 100b and the load power detection means 100c. Further, commercial power 100f is further connected to the connecting portion. The load power detection unit 100c is connected to a power load 100e such as an electronic device that consumes the power output from the fuel cell power generation system 100.

  In the conventional fuel cell power generation system 100 shown in FIG. 6, fuel gas and oxidant gas generated by fuel gas generation means such as a fuel processor (not shown in FIG. 6) are supplied to the fuel cell 100a. Then, in the fuel cell 100a, power generation is performed using the supplied fuel gas and oxidant gas. The output power output by the power generation in the fuel cell 100a is supplied to the power load 100e via the output control means 100b and the load power detection means 100c. In the power load 100e, the power supplied from the fuel cell power generation system 100 is consumed. At this time, excessive output power is stored by the storage battery 100d. Further, when the output power of the fuel cell 100a is insufficient with respect to the power consumption of the power load 100e, the power is replenished from the commercial power 100f.

  Here, the power generation operation of the conventional fuel cell power generation system will be described in detail based on an operation pattern example in one day.

  FIG. 7 is a pattern diagram schematically illustrating an operation pattern in a day of a conventional fuel cell power generation system. In FIG. 7, the vertical axis is the power axis, and the horizontal axis is the time axis.

  In FIG. 7, a curve 111 shows a change with time of power consumption consumed by the power load 100e, and a curve 112 shows a change with time of output power output from the fuel cell 100a. In FIG. 7, the maximum output power W1c indicates the maximum output power value that can be output by the fuel cell 100a. The minimum output power W1d indicates the minimum output power value that can be output by the fuel cell 100a.

  As shown by the curve 111 in FIG. 7, the power consumption in a general household is generally small in the time zone shown as the first time zone 101a from midnight to 5:00 in the early morning, but housework and the like are finished after getting up. In the time zone shown as the second time zone 101b up to about 13:00. The power consumption in the time zone shown as the third time zone 101c from 13:00 to 17:00 is small because the number of operating power loads 100e decreases, but the fourth time from 17:00 to around 23:00. The power consumption in the time zone indicated as the zone 101d increases again because the number of operating power loads 100e increases. Note that the power consumption in the time zone indicated as the fifth time zone 101e after going to bed is small, as in the time zone indicated as the first time zone 101a.

  In response to such fluctuations in power consumption in one day, the fuel cell 100a in the conventional fuel cell power generation system 100 outputs power as indicated by a curve 112 in FIG. Specifically, in the first time zone 101a shown in FIG. 7, the load power detection unit 100c of the fuel cell power generation system 100 starts the power generation operation of the fuel cell 100a in which the power consumption of the power load 100e is preset. When it is detected that the operation start power threshold value W1a, which is a threshold for performing the operation, has been exceeded for a predetermined time T1a or more, the power generation operation of the fuel cell 100a is activated (first activation). Then, the fuel cell 100a starts outputting electric power as indicated by a curve 112 after an operation preparation period Ts for generating fuel gas in the fuel processor or the like. When the output power of the fuel cell 100a reaches substantially the same power consumption as the power load 100e in the second time zone 101b, the output control means 100b detects the power load 100e detected by the load power detection means 100c. The output power of the fuel cell 100a is controlled between the maximum output power W1c and the minimum output power W1d so as to follow the fluctuation in power consumption. At this time, when the power consumption of the power load 100e exceeds the output power of the fuel cell 100a, the power shortage from the commercial power 100f is supplemented. Then, as shown in the third time zone 101c, when the power consumption of the power load 100e falls below the operation stop power threshold W1b for a predetermined time T1b or longer, the power generation operation of the fuel cell 100a is performed by the output control means 100b. Is stopped. At this time, the operation for generating the fuel gas such as the fuel processor is also stopped. Note that power supply to the power load 100e in a state where the power generation operation of the fuel cell 100a is stopped is performed by power supply from the commercial power 100f.

  Further, as shown in the third time zone 101c, the load power detection means 100c of the fuel cell power generation system 100 confirms that the power consumption of the power load 100e has exceeded the operation start power threshold W1a for a predetermined time T1a or more. When detected again, the power generation operation of the fuel cell 100a is restarted (second startup). Then, as in the first start-up, after the operation preparation period Ts, the fuel cell 100a resumes the output of electric power as indicated by the curve 112. Similarly to the case of the second time zone 101b, as shown in the fourth time zone 101d, the output control means 100b follows the fluctuation of the power consumption of the power load 100e detected by the load power detection means 100c. As described above, the output power of the fuel cell 100a is controlled between the maximum output power W1c and the minimum output power W1d.

  Further, as shown in the fifth time zone 101e, when the power consumption of the power load 100e falls below the operation stop power threshold W1b again for a predetermined time T1b or more, the power generation of the fuel cell 100a is performed by the output control means 100b. Operation for is stopped again. At this time, as in the case of the third time zone 101c, the operation of the fuel processor or the like is also stopped simultaneously. In this case as well, power is supplied to the power load 100e by supplying power from the commercial power 100f.

Thus, in the conventional fuel cell power generation system 100, the output power of the fuel cell 100a is controlled so as to follow the fluctuation of the power consumption of the power load 100e. Further, when the power consumption of the power load 100e shifts from a high state such as the second time zone 101b to a low state such as the third time zone 101c, the power consumption below the stop power threshold W1b is predetermined. When the operation continues for time T1b or longer, the power generation operation of the fuel cell 100a and the operation of the fuel processor, etc. are stopped.
JP 2000-299116 A JP 2002-352834 A

  However, the conventional fuel cell power generation system 100 described above has a problem that, for example, when the power generation operation of the operation pattern illustrated in FIG. 7 is performed, natural gas or the like is wasted by the second activation. It was.

  More specifically, in the conventional fuel cell power generation system 100, the fuel cell 100a, the fuel processor, and the like are activated twice a day as in the first activation and the second activation. In this case, when the power generation operation of the fuel cell 100a is stopped for a relatively long time like the fifth time zone 101e to the first time zone 101a, the fuel cell 100a and the fuel cell 100a and It is meaningful to stop the operation of the fuel processor or the like. However, when the power generation operation of the fuel cell 100a is stopped for a relatively short time as in the case of the third time zone 101c, the energy required for starting the fuel cell 100a, the fuel processor, etc. This is more energy than that consumed when the power generation operation of the fuel cell 100a is continued.

  That is, when the time during which the power consumption of the power load 100e is low is relatively short, the overall energy utilization efficiency is better if the power generation operation of the fuel cell 100a is continued.

  According to such a viewpoint, in the operation of the conventional fuel cell power generation system 100, natural gas or the like is consumed unnecessarily for starting the fuel cell 100a, the fuel processor, etc. that are originally unnecessary. There was a problem that overall energy use efficiency deteriorated. Such an unnecessary start-up operation is compared with other power generation systems such as an engine power generation system in a fuel cell power generation system that generates fuel gas by reforming raw materials such as natural gas (city gas). Then, since the start-up time is long, a lot of useless energy consumption occurs, causing further deterioration of the overall energy utilization efficiency.

  The present invention solves the above-mentioned conventional problems, and prevents unnecessary stoppage of the power generation operation by changing the condition of the operation stop determination of the power generation unit according to the human activity cycle and the like. An object of the present invention is to provide a power generation apparatus with excellent energy use efficiency capable of suppressing energy consumption and an operation method thereof.

And in order to achieve these objects, a power generator according to the present invention includes a power generation unit that is a fuel cell, load power detection means that detects load power supplied to a load from a power source including the power generation unit, A power generation apparatus comprising: an operation stop determination means for stopping the power generation operation of the power generation unit based on the load power detected by the load power detection means and a stop condition; and a stop condition setting means for setting the stop condition a is, before Symbol operation stop decision means, (i) when said load power detecting means the load power detected time below the instantaneous power threshold, continues for a predetermined time or more, the power generation operation of the generator unit the stop, integrated electricity of the load power the load power detecting unit detects in (ii) a predetermined time, if less than the integrated power threshold, stops the power generation operation of the power generation unit, or, (i i) When the frequency at which the load power detected by the load power detection means at a predetermined time falls below an instantaneous power threshold is a predetermined frequency or more, the power generation operation of the power generation unit is stopped, and the stop condition setting means is , (Iv) a setting in which the instantaneous power threshold or the integrated power threshold is smaller in a time zone in which the average value of the load power is larger for a plurality of time zones, and (v) the load for a plurality of time zones. A setting in which the predetermined time is longer in the time zone in which the average value of power is larger, and (vi) the predetermined frequency in the time zone in which the average value of the load power is larger than a plurality of time zones. Is set to at least one of the large settings . With such a configuration, an individual stop condition suitable for each time zone is defined, so that it is possible to prevent an unnecessary stop of the power generation device in a time zone where power generation is necessary, and in a time zone where power generation is unnecessary. An effect is obtained that unnecessary operation of the power generation device can be prevented.

  Further, the time zone is two time zones obtained by dividing one day of a time zone including at least 2 o'clock and a time zone including at least 14:00 into two. The time zones are three time zones obtained by dividing one day into a time zone including at least 2 o'clock, a time zone including at least 10 o'clock, and a time zone including at least 18 o'clock. In addition, the time zone is divided into four parts by dividing one day into a time zone including at least 2 o'clock, a time zone including at least 8 o'clock, a time zone including at least 14 o'clock, and a time zone including at least 20 o'clock. It is a time zone. With this configuration, the day is divided into two, three, or four divisions based on 2 o'clock when power demand is generally low, so the power generation operation of the power generation unit is stopped in two, three, or four time zones. The effect that the determination which concerns on can be performed effectively is acquired.

  The time zone and the stop condition are set in advance. With such a configuration, since the time zone and the stop condition are set in advance, there is an effect that unnecessary operation of the power generation device can be prevented with a simple configuration. Here, the state in which the time zone and the stop condition are set in advance refers to a state in which the time zone and the stop condition are set as initial values when the power generation apparatus is shipped.

  Further, the apparatus further comprises learning means for learning at least the time zone and the stop condition based on accumulation of data of the load power detected by the load power detection means, and the time zone and the stop obtained by the learning. The condition is set by the stop condition setting means. With such a configuration, it is possible to cope with various power demands by using the time zone and the stop condition obtained by learning based on the accumulation of data. Thus, it is possible to prevent an unnecessary stop and to prevent unnecessary operation of the power generation apparatus in a time zone where power generation is unnecessary.

A method for operating a power generator according to the present invention includes: a power generation unit that is a fuel cell ; and a load power detection unit that detects load power supplied to a load from a power source including the power generation unit. (I) a setting in which the instantaneous power threshold or the integrated power threshold is smaller in a time zone in which the average value of the load power is larger than a plurality of time zones, and (ii) The time period in which the average value of the load power is larger is set to have a longer predetermined time, and (iii) the time period in which the average value of the load power is larger for a plurality of time periods has a predetermined frequency. At least one of the large settings is set, and based on the setting, (iv) the time when the load power detected by the load power detection means falls below the instantaneous power threshold continues for the predetermined time or more. The power generation unit (V) when the integrated power amount of the load power detected by the load power detection means at the predetermined time is below the integrated power threshold, stop the power generation operation of the power generation unit; Alternatively, (vi) when the frequency at which the load power detected by the load power detection means at the predetermined time falls below the instantaneous power threshold is equal to or higher than the predetermined frequency, the power generation operation of the power generation unit is stopped . With such a configuration, an individual stop condition suitable for each time zone is defined, so that it is possible to prevent an unnecessary stop of the power generation device in a time zone where power generation is necessary, and in a time zone where power generation is unnecessary. An effect is obtained that unnecessary operation of the power generation device can be prevented.

  The above object, other objects, features, and advantages of the present invention will become apparent from the following detailed description of the preferred embodiments with reference to the accompanying drawings.

  According to the present invention, the energy that can prevent unnecessary stoppage of the power generation operation by changing the condition of the operation stop determination of the power generation unit according to the human activity cycle, etc., and thereby can suppress wasteful energy consumption. It is possible to provide a power generation apparatus with excellent utilization efficiency and an operation method thereof.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings, taking a fuel cell power generation system as an example of a power generation system.

(Embodiment 1)
In the first embodiment of the present invention, an embodiment will be described in which the power threshold condition related to the power generation operation of the fuel cell is changed in accordance with the usage status of the fuel cell power generation system.

  First, the configuration of the fuel cell power generation system according to Embodiment 1 of the present invention will be described with reference to the drawings.

  FIG. 5 is a block diagram schematically showing the configuration of the fuel cell power generation system according to Embodiment 1 of the present invention.

  As shown in FIG. 5, the fuel cell power generation system 200 according to the present embodiment generates a fuel gas containing abundant hydrogen by converting a raw material such as natural gas into hydrogen by a steam reforming reaction, which will be described later. A fuel processor 201 supplied to the fuel cell 202, an air blower 203 for supplying air as an oxidant gas to the fuel cell 202, a fuel gas supplied from the fuel processor 201, and an oxidant supplied from the air blower 203 Consumption of a fuel cell 202 that generates power using gas, an inverter 204 that converts DC power generated by the fuel cell 202 into AC power, and a power load 213 that consumes AC power output from the inverter 204 The load power detection means 205 capable of detecting power and the operation of the fuel cell power generation system 200 based on the output signal of the load power detection means 205. The start and has stopped, and a series of start of the operation until the start power generation operation, as well as a control unit 206 for controlling the power generation operation of the fuel cell 202 after the start of power generation or the like. As shown in FIG. 5, the load power 213 is also connected to the commercial power 214.

  The control unit 206 includes power amount change means 207 that changes the output power amount of the fuel cell power generation system 200 so as to follow the power consumption of the power load 213 detected by the load power detection means 205. In addition, the control unit 206 detects that the power consumption of the power load 213 detected by the load power detection unit 205 falls below a preset power threshold for stopping the power generation operation of the fuel cell 202 for a preset time. In this case, or when the frequency falls below a predetermined frequency set in advance within the predetermined time, an operation stop determination unit 209 for stopping the power generation operation of the fuel cell 202 is provided. In addition, the control unit 206 includes a time zone setting unit 208 that sets a time zone (in this embodiment, setting a daytime or nighttime zone) based on the recognition of the current time. In addition, the control unit 206 includes a learning unit 215 that stores and learns a power consumption pattern of the power load 213 in a predetermined period. Further, the control unit 206 has power threshold conditions that are conditions for causing the operation stop determination unit 209 to stop the power generation operation of the fuel cell 202 based on the output signal of the time zone setting unit 208 or the learning unit 215. A power threshold setting unit 210, a time setting unit 211, and a frequency setting unit 212 are provided for setting a time condition, a frequency condition, and the like. A plurality of power threshold conditions, time conditions, frequency conditions, etc. are stored in advance in the power threshold setting means 210, the time setting means 211, and the frequency setting means 212, and the output of the time zone setting means 208 or the learning means 215 is stored. Depending on the signal, the optimum power threshold condition, time condition, frequency condition, etc. suitable for the situation are set in the operation stop determination means 209. Here, the control unit 206 is composed of, for example, a microcomputer, and each means 207 to 212 and 215 is realized by software stored in the memory of the microcomputer. Each of the means 210 to 212 and 215 constitutes a condition setting means 220.

  As described above, the load power detection unit 205 is connected to the power load 213. The power load 213 is a power load that consumes at least either the power generated by the fuel cell power generation system 200 or the commercial power 214. Examples of the power load 213 include household electronic devices.

  In the fuel cell power generation system 200 shown in FIG. 5, the fuel gas generated by the fuel processor 201 and the oxidant gas supplied from the air blower 203 are supplied to the fuel cell 202. Then, in the fuel cell 202, the supplied fuel gas and oxidant gas are used to generate power to output DC power. The DC power output from the fuel cell 202 is input to the inverter 204. The inverter 204 converts the DC power supplied from the fuel cell 202 into AC power and outputs it. The AC power output from the inverter 204 is supplied to the power load 213 via the load power detection unit 205. In the power load 213, the power supplied from the fuel cell power generation system 200 is consumed. At this time, excessive output power is stored by a storage battery or the like not particularly shown in FIG. Further, when the output power of the fuel cell 202 is insufficient with respect to the power consumption of the power load 213, power is replenished from the commercial power 214. Further, the power generation state of the fuel cell 202 is appropriately controlled by the control unit 206.

  Next, the power generation operation of the fuel cell power generation system according to Embodiment 1 of the present invention will be described in detail with reference to the drawings based on one day operation pattern examples.

  FIG. 1 is a pattern diagram schematically illustrating an operation pattern for one day of the fuel cell power generation system according to Embodiment 1 of the present invention. In FIG. 1, the vertical axis is the power axis, and the horizontal axis is the time axis.

  In FIG. 1, a curve 311 shows a change with time of power consumption consumed by the power load 213, and a curve 312 shows a change with time of output power output from the fuel cell 202. In FIG. 1, the maximum output power W1c indicates the maximum output power value that the fuel cell 202 can output. Further, the minimum output power W1d indicates the minimum output power value that the fuel cell 202 can output.

  As shown by the curve 311 in FIG. 1, the power consumption in a general household is generally small in the time zone indicated as the first time zone 301a from midnight to 6:00 in the early morning. However, in the time zone shown as the second time zone 301b from 6:00 to 12:00 in the early morning, the power load 213 is frequently used due to housework or the like, and thus power consumption is large. On the other hand, in the time zone indicated as the third time zone 301c from 12:00 noon to 18:00 in the evening, the number of operating power loads 213 decreases, and thus the power consumption is small. However, in the time zone shown as the fourth time zone 301d from 18:00 in the evening to 23:00 in the evening, the number of power loads 213 operating due to housework or the like increases, so the power consumption increases again. Note that, in the time zone indicated as the fifth time zone 301e from midnight to midnight, the power consumption of the power load 213 is small due to sleeping or the like.

  The fuel cell 202 in the fuel cell power generation system 200 according to the present embodiment outputs power as shown by a curve 312 in FIG. 1 in response to such fluctuations in power consumption of the power load 213 in one day. Specifically, as shown in FIG. 1, an operation start power threshold that is a power threshold for the fuel cell 202 in which the power consumption of the power load 213 is preset in the first time zone 301 a to start a power generation operation. When the load power detection means 205 of the fuel cell power generation system 200 detects that W1a has been exceeded for a predetermined time T1a or more, the power generation operation of the fuel cell 202 is started. Then, the fuel cell 202 starts outputting power as indicated by a curve 312 after an operation preparation period Ts for fuel gas generation or the like in the fuel processor 201 has elapsed. When the output power of the fuel cell 202 reaches substantially the same as the power consumption of the power load 213 in the second time zone 301b, the power amount change means 207 detects the power load detected by the load power detection means 205. The output power of the fuel cell 202 is controlled between the maximum output power W1c and the minimum output power W1d so as to follow the fluctuation of the power consumption of 213. At this time, when the power consumption of the power load 213 exceeds the output power of the fuel cell 202, the power shortage from the commercial power 214 is supplemented.

  In the present embodiment, as the operation stop power threshold for stopping the power generation operation of the fuel cell 202, the operation stop power threshold W1bd for the time zone in which the power load 213 operates relatively frequently and the power load 213 are excessive. The operation stop power threshold W1bn for a time zone that is not frequently operated is stored in advance in the power threshold setting unit 210. Here, in the present embodiment, as shown in FIG. 1, when the shutdown power threshold W1bd and the shutdown power threshold W1bn are compared, the shutdown power threshold W1bd is set lower than the shutdown power threshold W1bn. Has been. By the way, generally, the time zone in which the power load 213 operates relatively frequently is daytime, and the time zone in which the power load 213 does not operate frequently is nighttime. Therefore, in the present embodiment, when the current time is from 6:00 to 18:00 indicated as the second to third time zones 301b to 301c, it is determined to be daytime, and the current time is set to the first time zone 301a and the fourth time zone. The time zone setting means 208 is set in advance so as to determine that it is nighttime when it is 18:00 to 6 o'clock shown as the time zones 301d to 301e of ˜5. Then, as shown in FIG. 1, when the time zone setting means 208 determines that it is a daytime time zone based on the recognition of the current time, the shutdown power threshold W1bd is set, and based on the recognition of the current time. When the time zone setting unit 208 determines that it is a night time zone, the power threshold value setting unit 210 sets the operation stop power threshold value W1bn for the operation stop determination unit 209. In any case, the time setting unit 211 sets a predetermined time T1b for the operation stop determination unit 209. Here, as described above, when the shutdown power threshold W1bd and the shutdown power threshold W1bn are compared, the shutdown power threshold W1bd is set lower than the shutdown power threshold W1bn. By setting the two different shutdown power thresholds in this way, the power generation operation of the fuel cell 202 is not frequently stopped in the daytime period when the power load 213 is generally operated relatively frequently. Consideration. That is, as shown in the third time zone 301c shown in FIG. 1, even when the power consumption of the power load 213 is lower than the shutdown power threshold W1bd, the lowering time is less than the predetermined time T1b. The power generation operation of the fuel cell 202 is not stopped. In this case, the operation of the fuel processor 201 for generating the fuel gas is not stopped. And as shown in the 3rd time slot | zone 301c of FIG. 1, the fuel cell 202 continues outputting electric power with the minimum output electric power W1d. In this third time zone 301c, the minimum output power W1d exceeds the power consumption of the power load 213. However, the excessive output generated when the fuel cell 202 continues to output power with the minimum output power W1d. Electric power is stored by a storage battery or the like not specifically shown in FIG.

  Also, as shown in the fourth time zone 301d, when the load power detection means 205 of the fuel cell power generation system 200 detects that the power consumption of the power load 213 has increased again, the fuel cell 202 is shown in the curve 312. Increase (rise) the output of. In this case, as in the case of the second time zone 301b, as shown in the fourth time zone 301d, the power amount changing unit 207 is responsive to fluctuations in the power consumption of the power load 213 detected by the load power detecting unit 205. The output power of the fuel cell 202 is controlled between the maximum output power W1c and the minimum output power W1d so as to follow. At this time, when the power consumption of the power load 213 exceeds the output power of the fuel cell 202, the power shortage from the commercial power 214 is supplemented.

  On the other hand, as shown in the fifth time zone 301e, when the load power detection unit 205 detects that the power consumption of the power load 213 has dropped below the operation stop power threshold W1bn for a predetermined time T1b or more, The power generation operation of the fuel cell 202 is stopped by the operation stop determination unit 209. At this time, the operation of the fuel processor 201 is also stopped. At this time, power is supplied to the power load 213 by supplying power from the commercial power 214.

  As described above, in the fuel cell power generation system 200 according to the present embodiment, the output power of the fuel cell 202 is controlled so as to follow the fluctuation of the power consumption of the power load 213. Even when the power consumption of the power load 213 shifts from a high state such as the second time zone 301b to a low state such as the third time zone 301c, the power consumption below the shutdown power threshold W1bd When it does not continue for the predetermined time T1b or longer, the power generation operation of the fuel cell 202 is not stopped. On the other hand, when the power consumption of the power load 213 shifts from a high state such as the fourth time zone 301d to a low state such as the fifth time zone 301e, the power consumption below the operation stop power threshold W1bn is predetermined. In this case, the power generation operation of the fuel cell 202 is stopped.

  According to the fuel cell power generation system 200 according to the present embodiment, as the operation stop power threshold W1b that is a condition for stopping the power generation operation of the fuel cell 202, the operation stop power threshold W1bd having different power values such as W1bd <W1bn. Alternatively, the operation stop power threshold W1bn is set in the operation stop determination unit 209 based on the determination by the time zone setting unit 208. Therefore, it is possible to prevent an unnecessary stop of the power generation operation of the fuel cell 202 even in a time zone in which the power consumption of the power load 213 is reduced as in the time zone indicated as the third time zone 301c. As a result, it is possible to reduce wasteful energy consumption (particularly, energy consumption during the operation preparation period Ts related to the start of the fuel processor 201) related to the start of the power generation operation of the fuel cell 202. It becomes possible to continue high power generation operation.

  In the present embodiment, the operation stop power threshold W1bd and the operation stop power threshold W1bn are set by the user of the fuel cell power generation system 200 (or the driver or the administrator) via input means not particularly shown in FIG. The power consumption pattern of the power load 213 on a weekly basis (or on a monthly or seasonal basis) may be set in the power threshold setting unit 210 by the learning unit 215 storing and learning. Also good. In this case, for example, the learning unit 215 extracts the third time zone 301c and the fifth time zone 301e, which are the time zones in which the power consumption of the power load 213 in FIG. A relatively small shutdown power threshold W1bd is set for the third time zone 301c with a large amount of power, and a relatively large shutdown power threshold W1bn for the fifth time zone 301e with a relatively small amount of power consumption. May be configured to set.

  In the present embodiment, it is assumed that the time zone in which the power load 213 operates relatively frequently is daytime, and that the time zone in which the power load 213 does not operate frequently is nighttime. In the present embodiment, the time zone setting unit 208 makes day / night judgments, but the user (or the driver or the manager) of the fuel cell power generation system 200 judges and is not particularly shown in FIG. You may set uniquely via an input means.

  In the present embodiment, the daytime zone and the nighttime zone are each set as 12 hours, but the daytime zone may be set longer than 12 hours, or the nighttime zone. May be set longer than 12 hours.

  In this embodiment, one day is divided into two every 12 hours. However, the present invention is not limited to such a division method, and any division form may be adopted.

  Also, depending on the human activity cycle, the time zone in which the power load 213 operates relatively frequently may be nighttime, and the time zone in which the power load 213 does not operate too often may be daytime. It is also conceivable that the power consumption of the power load 213 fluctuates completely regardless of the day / night time zone. In such a case, the learning unit 215 recognizes the fluctuation pattern of the power consumption of the power load 213 by the learning function, and selects the operation stop power threshold W1bd or the operation stop power threshold W1bn based on the recognition. The stop determination unit 209 is set. By adopting such a configuration, it is possible to prevent an unnecessary stop of the power generation operation of the fuel cell 202 during a time period in which the power load 213 operates relatively frequently.

  In the present embodiment, the operation stop power threshold is set based on the output signal of the time zone setting means 208 or the learning means 215. However, the operation stop power threshold is set by the fuel cell power generation. A user of the system 200 (or a driver or a manager) may perform the operation independently through input means not specifically shown in FIG.

  In the present embodiment, the shutdown power threshold W1bd and the shutdown power threshold W1bn are described as thresholds for the instantaneous power, but the thresholds for the integrated power detected by the load power detection unit 205 at the predetermined time T1b are also described. good. Even with such a configuration, it is possible to obtain the same effect as the present embodiment.

(Embodiment 2)
In the second embodiment of the present invention, an embodiment in which a frequency condition is added to the conditions related to the start or stop of the power generation operation of the fuel cell will be described with respect to the operation conditions of the fuel cell in the fuel cell power generation system.

  The configuration of the fuel cell power generation system according to Embodiment 2 of the present invention is the same as the configuration of the fuel cell power generation system 200 shown in Embodiment 1. Therefore, the description regarding the configuration of the fuel cell power generation system according to Embodiment 2 of the present invention is omitted here. In addition, an example of an operation pattern for one day of the fuel cell power generation system according to Embodiment 2 of the present invention is similar to the example of operation pattern shown in Embodiment 1. Therefore, in this embodiment, differences from Embodiment 1 will be described in detail.

  FIG. 2 is a pattern diagram schematically illustrating one day operation pattern of the fuel cell power generation system according to Embodiment 2 of the present invention. In FIG. 2, the vertical axis is the power axis, and the horizontal axis is the time axis.

  In FIG. 2, a curve 321 indicates a change with time in power consumption consumed by the power load 213, and a curve 322 indicates a change with time in output power output from the fuel cell 202. In FIG. 2, the maximum output power W2c indicates the maximum output power value that the fuel cell 202 can output. The minimum output power W2d indicates the minimum output power value that the fuel cell 202 can output.

  The fuel cell 202 in the fuel cell power generation system 200 according to the present embodiment responds to fluctuations in power consumption consumed by the power load 213 as shown by the curve 321 in FIG. 2 as shown by the curve 322 in FIG. Output. Specifically, in the first time zone 301a shown in FIG. 2, the load power detection unit 205 of the fuel cell power generation system 200 starts the power generation operation of the fuel cell 202 in which the power consumption of the power load 213 is set in advance. When it is detected that the operation start power threshold value W2a, which is a power threshold value for exceeding, exceeds a predetermined frequency F2a within a predetermined time T2a, the power generation operation of the fuel cell 202 is started. Here, the reason why the frequency F2a is added as the starting condition of the fuel cell 202 is that even if the power consumption of the power load 213 instantaneously falls below the operation start power threshold W2a within the predetermined time T2a, This is to ensure that the operation is started.

  The determination as to whether or not the power consumption of the power load 213 exceeds the operation start power threshold W2a within a predetermined time T2a by a predetermined frequency F2a or more is performed based on the following concept. That is, for example, it is assumed that the predetermined time T2a is 1 hour, the sampling period of the power consumption value of the power load 213 by the load power detection means 205 is 1 time / second, and the predetermined frequency F2a is 80%. In this case, the load power detection unit 205 samples the power consumption value of the power load 213 a total of 3600 times at the predetermined time T2a. When the load power detection unit 205 counts the power consumption value of the power load 213 exceeding the operation start power threshold W2a more than 2880 times corresponding to a predetermined frequency F2a (here, 80%), the power generation of the fuel cell 202 is performed. The control unit 206 determines that the operation is to be started. It should be noted that such determination regarding the necessity of starting the power generation operation of the fuel cell 202 is sequentially performed during the operation of the control unit 206 of the fuel cell power generation system 200. Here, although not shown in FIG. 5, the control unit 206 counts the power consumption value of the power load 213 that exceeds the operation start power threshold W2a, an integration unit that integrates the number of times the count unit outputs, A command unit that outputs a command related to activation of the power generation operation of the fuel cell 202 based on the output signal output from the integration unit, and a startup that activates the power generation operation of the fuel cell 202 based on the output signal output from the command unit And other parts.

  When the power generation operation of the fuel cell 202 is started, the fuel cell 202 starts outputting electric power as indicated by a curve 322 after an operation preparation period Ts for fuel gas generation or the like in the fuel processor 201 has elapsed. When the output power of the fuel cell 202 reaches substantially the same as the power consumption of the power load 213 in the second time zone 301b, the power amount change means 207 detects the power load detected by the load power detection means 205. The output power of the fuel cell 202 is controlled between the maximum output power W2c and the minimum output power W2d so as to follow the fluctuation of the power consumption of 213. At this time, when the power consumption of the power load 213 exceeds the output power of the fuel cell 202, the power shortage from the commercial power 214 is supplemented.

  Also in the present embodiment, as the operation stop power threshold for stopping the power generation operation of the fuel cell 202, the operation stop power threshold W2bd for the time zone in which the power load 213 operates relatively frequently and the power load 213 are An operation stop power threshold W2bn for a time zone that does not operate too frequently is stored in advance in the power threshold setting means 210. Here, the relationship between the shutdown power threshold W2bd and the shutdown power threshold W2bn is the same as in the first embodiment. In this embodiment, the time setting unit 211 and the frequency setting unit 212 each store a predetermined time T2b and a predetermined frequency F2b in advance.

  Similarly to the case of the first embodiment, when the time zone setting unit 208 determines that it is a daytime time zone based on the current time, the operation stop power threshold W2bd is set, and the night time zone is set. When it is determined that there is an operation stoppage power threshold W2bn, the power threshold setting unit 210 sets the operation stop determination unit 209 with respect to the operation stop determination unit 209. At this time, in any case, the time setting unit 211 and the frequency setting unit 212 set the predetermined time T2b and the predetermined frequency F2b to the operation stop determination unit 209. As shown in the third time zone 301c of FIG. 2, even when the power consumption of the power load 213 is lower than the shutdown power threshold W2bd, the frequency of the power load 213 is less than the predetermined frequency F2b within the predetermined time T2b. In this case, the power generation operation of the fuel cell 202 is not stopped. In this case, the operation of the fuel processor 201 for generating the fuel gas is not stopped. At this time, the power generation operation of the fuel cell 202 is stopped when the frequency of the operation stop power threshold W2bd being lower than the predetermined frequency F2b within the predetermined time T2b. In this case, the operation for generating the fuel gas of the fuel processor 201 is also stopped. More specifically, for example, when F2b = 70%, even if the power consumption exceeding the shutdown power threshold W2bd occurs instantaneously like the power consumption 321f in the third time zone 301c, the shutdown power When the load power detection means 205 detects that the threshold W2bd falls below 70% or more within the predetermined time T2b (that is, when the frequency of the power consumption 321f within the predetermined time T2b is less than 30%). The power generation operation of the fuel cell 202 is stopped. If the power generation operation of the fuel cell 202 is not stopped, the fuel cell 202 continues to output power with the minimum output power W2d as shown in the third time zone 301c of FIG. In this third time zone 301c, the minimum output power W2d exceeds the power consumption of the power load 213. However, the excessive output generated when the fuel cell 202 continues to output power with the minimum output power W2d. Electric power is stored by a storage battery or the like as in the first embodiment.

  Also, as shown in the fourth time zone 301d, when the load power detection means 205 of the fuel cell power generation system 200 detects that the power consumption of the power load 213 has increased again, the fuel cell 202 is shown in the curve 322. Increase (rise) the output of. In this case, as in the case of the second time zone 301b, as shown in the fourth time zone 301d, the power amount changing unit 207 is responsive to fluctuations in the power consumption of the power load 213 detected by the load power detecting unit 205. The output power of the fuel cell 202 is controlled between the maximum output power W2c and the minimum output power W2d so as to follow. At this time, when the power consumption of the power load 213 exceeds the output power of the fuel cell 202, the power shortage from the commercial power 214 is supplemented.

  On the other hand, as shown in the fifth time zone 301e, the load power detection unit 205 detects that the power consumption of the power load 213 has fallen below the shutdown power threshold W2bn by a predetermined frequency F2b or more within a predetermined time T2b. In this case, the power generation operation of the fuel cell 202 is stopped by the operation stop determination unit 209. At this time, the operation of the fuel processor 201 is also stopped. More specifically, for example, when F2b = 70%, even when power consumption exceeding the shutdown power threshold W2bn occurs instantaneously like the power consumption 321g in the fifth time zone 301e, the shutdown power When the load power detection means 205 detects that the threshold W2bn is less than 70% within the predetermined time T2b (that is, when the frequency of the power consumption 321g within the predetermined time T2b is less than 30%). The power generation operation of the fuel cell 202 is stopped. At this time, power is supplied to the power load 213 by supplying power from the commercial power 214.

  Thus, in the present embodiment, even when the power consumption of the power load 213 shifts from a high state such as the second time zone 301b to a low state such as the third time zone 301c, the operation is stopped. When power consumption equal to or less than the power threshold W2bd does not occur more than a predetermined frequency F2b within a predetermined time T2b, the power generation operation of the fuel cell 202 is not stopped. On the other hand, when the power consumption of the power load 213 shifts from a high state such as the fourth time zone 301d to a low state such as the fifth time zone 301e, the power consumption below the operation stop power threshold W2bn is predetermined. If the frequency F2b or more occurs within the time T2b, the power generation operation of the fuel cell 202 is stopped.

  Even with such a configuration, the same effect as in the first embodiment can be obtained. That is, since wasteful energy consumption related to the start of the power generation operation of the fuel cell 202 can be reduced, it is possible to continue a good power generation operation with high energy utilization efficiency. Other points are the same as those in the first embodiment.

(Embodiment 3)
In Embodiment 3 of the present invention, an embodiment will be described in which the time condition related to the power generation operation of the fuel cell is changed in accordance with the usage status of the fuel cell power generation system.

  The configuration of the fuel cell power generation system according to Embodiment 3 of the present invention is also the same as the configuration of the fuel cell power generation system 200 shown in Embodiment 1. Therefore, the description regarding the configuration of the fuel cell power generation system according to Embodiment 3 of the present invention is also omitted here. In addition, an example of an operation pattern in one day of the fuel cell power generation system according to Embodiment 3 of the present invention is similar to the example of operation pattern shown in Embodiment 1. Therefore, also in the present embodiment, differences from the first embodiment will be described in detail.

  FIG. 3 is a pattern diagram schematically illustrating one day operation pattern of the fuel cell power generation system according to Embodiment 3 of the present invention. In FIG. 3, the vertical axis is the power axis, and the horizontal axis is the time axis.

  In FIG. 3, a curve 331 indicates a change with time in power consumption consumed by the power load 213, and a curve 332 indicates a change with time in output power output from the fuel cell 202. In FIG. 3, the maximum output power W3c indicates the maximum output power value that the fuel cell 202 can output. The minimum output power W3d indicates the minimum output power value that the fuel cell 202 can output.

  The fuel cell 202 in the fuel cell power generation system 200 according to the present embodiment responds to fluctuations in power consumption consumed by the power load 213 as shown by a curve 331 in FIG. 3, as shown by a curve 332 in FIG. 3. Output. Specifically, as shown in FIG. 3, an operation start power threshold that is a power threshold for the fuel cell 202 in which the power consumption of the power load 213 is preset in the first time zone 301 a to start the power generation operation. When the load power detection means 205 of the fuel cell power generation system 200 detects that W3a has been exceeded for a predetermined time T3a or more, the power generation operation of the fuel cell 202 is started. Then, the fuel cell 202 starts outputting electric power as indicated by a curve 332 after the operation preparation period Ts for fuel gas generation or the like in the fuel processor 201 has elapsed. When the output power of the fuel cell 202 reaches substantially the same as the power consumption of the power load 213 in the second time zone 301b, the power amount change means 207 detects the power load detected by the load power detection means 205. The output power of the fuel cell 202 is controlled between the maximum output power W3c and the minimum output power W3d so as to follow the fluctuation of the power consumption of 213. At this time, when the power consumption of the power load 213 exceeds the output power of the fuel cell 202, the power shortage from the commercial power 214 is supplemented.

  In the present embodiment, the operation stop power threshold W3b that is equal to each other is used as the operation stop power threshold for stopping the power generation operation of the fuel cell 202. The operation stop power threshold W3b is stored in the power threshold setting unit 210 in advance. However, in the present embodiment, a predetermined time T3bd for a time zone in which the power load 213 operates relatively frequently and a predetermined time T3bn for a time zone in which the power load 213 does not operate frequently are time. Each is stored in the setting means 211 in advance. Here, the relationship between the predetermined time T3bd and the predetermined time T3bn is set so that the predetermined time T3bd is longer than the predetermined time T3bn.

  Similarly to the case of the first embodiment, when the time zone setting unit 208 determines that it is a daytime time zone based on the current time, the predetermined time T3bd is also set, and the time zone is a night time zone. If it is determined, the time setting unit 211 sets the predetermined time T3bn to the operation stop determination unit 209. At this time, in any case, the power threshold setting unit 210 sets the operation stop power threshold W3b for the operation stop determination unit 209. And as shown in the 3rd time slot | zone 301c of FIG. 3, even when the power consumption of the electric power load 213 is less than the operation stop electric power threshold value W3b, when the time when it was less than predetermined time T3bd, The power generation operation of the fuel cell 202 is not stopped. In this case, the operation of the fuel processor 201 for generating the fuel gas is not stopped. At this time, the power generation operation of the fuel cell 202 is stopped when the time during which the operation has stopped below the stop power threshold W3b is equal to or longer than the predetermined time T3bd. In this case, the operation for generating the fuel gas of the fuel processor 201 is also stopped. If the power generation operation of the fuel cell 202 is not stopped, the fuel cell 202 continues to output power at the minimum output power W3d as shown in the third time zone 301c of FIG. In this third time zone 301c, the minimum output power W3d exceeds the power consumption of the power load 213, but an excessive amount is generated when the fuel cell 202 continues to output power with the minimum output power W3d. Electric power is stored by a storage battery or the like as in the first embodiment.

  Also, as shown in the fourth time zone 301d, when the load power detection means 205 of the fuel cell power generation system 200 detects that the power consumption of the power load 213 has increased again, the fuel cell 202 has a power as indicated by a curve 332. Increase (rise) the output of. In this case, as in the case of the second time zone 301b, as shown in the fourth time zone 301d, the power amount changing unit 207 is responsive to fluctuations in the power consumption of the power load 213 detected by the load power detecting unit 205. The output power of the fuel cell 202 is controlled between the maximum output power W3c and the minimum output power W3d so as to follow. At this time, when the power consumption of the power load 213 exceeds the output power of the fuel cell 202, the power shortage from the commercial power 214 is supplemented.

  On the other hand, as shown in the fifth time zone 301e, when the load power detection unit 205 detects that the power consumption of the power load 213 is lower than the operation stop power threshold W3b by a predetermined time T3bn, the operation is stopped. The power generation operation of the fuel cell 202 is stopped by the determination unit 209. At this time, the operation of the fuel processor 201 is also stopped. At this time, power is supplied to the power load 213 by supplying power from the commercial power 214.

  Thus, in the present embodiment, even when the power consumption of the power load 213 shifts from a high state such as the second time zone 301b to a low state such as the third time zone 301c, the operation is stopped. When the power consumption below the power threshold W3b does not continue for the predetermined time T3bd or longer, the power generation operation of the fuel cell 202 is not stopped. On the other hand, when the power consumption of the power load 213 shifts from a high state such as the fourth time zone 301d to a low state such as the fifth time zone 301e, the power consumption below the operation stop power threshold W3b is predetermined. In this case, the power generation operation of the fuel cell 202 is stopped.

  Even with such a configuration, an unnecessary stop of the power generation operation of the fuel cell 202 can be prevented, so that the same effect as in the first embodiment can be obtained.

  In the present embodiment, the predetermined time T3bd and the predetermined time T3bn may be set uniquely by the user (or the driver or the administrator) of the fuel cell power generation system 200, or in units of one week ( Alternatively, the learning unit 215 may store and learn the power consumption pattern of the power load 213 in units of one month or seasons, and may be set in the time setting unit 211. A specific setting method is the same as the method described in the first embodiment.

  In the present embodiment, the stop power threshold W3b is described as a threshold for the instantaneous power, but it may be a threshold for the integrated power detected by the load power detector 205 at the predetermined time T3bd or the predetermined time T3bn. . Other points are the same as those in the first embodiment.

(Embodiment 4)
In the fourth embodiment of the present invention, an embodiment in which the frequency condition relating to the power generation operation of the fuel cell is changed according to the usage status of the fuel cell power generation system will be described.

  The configuration of the fuel cell power generation system according to Embodiment 4 of the present invention is also the same as that of the fuel cell power generation system 200 shown in Embodiment 1. Therefore, the description regarding the configuration of the fuel cell power generation system according to Embodiment 4 of the present invention is also omitted here. In addition, an example of an operation pattern for one day of the fuel cell power generation system according to Embodiment 4 of the present invention is similar to the example of operation pattern shown in Embodiment 1. Therefore, also in the present embodiment, differences from the first embodiment will be described in detail.

  FIG. 4 is a pattern diagram schematically illustrating one day operation pattern of the fuel cell power generation system according to Embodiment 4 of the present invention. In FIG. 4, the vertical axis is the power axis, and the horizontal axis is the time axis.

  In FIG. 4, a curve 341 shows a change with time of power consumption consumed by the power load 213, and a curve 342 shows a change with time of output power output from the fuel cell 202. In FIG. 4, the maximum output power W4c indicates the maximum output power value that the fuel cell 202 can output. The minimum output power W4d indicates the minimum output power value that the fuel cell 202 can output.

  The fuel cell 202 in the fuel cell power generation system 200 according to the present embodiment responds to fluctuations in power consumption consumed by the power load 213 as shown by the curve 341 in FIG. 4 as shown by the curve 342 in FIG. Output. Specifically, in the first time zone 301 a shown in FIG. 4, the load power detection unit 205 of the fuel cell power generation system 200 starts the power generation operation of the fuel cell 202 in which the power consumption of the power load 213 is set in advance. When it is detected that the operation start power threshold value W4a, which is a power threshold value, exceeds a predetermined frequency F4a within a predetermined time T4a, the power generation operation of the fuel cell 202 is started.

  When the power generation operation of the fuel cell 202 is started, the fuel cell 202 starts outputting electric power as indicated by a curve 342 after an operation preparation period Ts for fuel gas generation or the like in the fuel processor 201 elapses. When the output power of the fuel cell 202 reaches substantially the same as the power consumption of the power load 213 in the second time zone 301b, the power amount change means 207 detects the power load detected by the load power detection means 205. The output power of the fuel cell 202 is controlled between the maximum output power W4c and the minimum output power W4d so as to follow the fluctuation of the power consumption of 213. At this time, when the power consumption of the power load 213 exceeds the output power of the fuel cell 202, the power shortage from the commercial power 214 is supplemented.

  Also in the present embodiment, the operation stop power threshold W4b that is equal to each other is used as the operation stop power threshold for stopping the power generation operation of the fuel cell 202. This operation stop power threshold W4b is stored in the power threshold setting means 210 in advance. However, in the present embodiment, a predetermined frequency F4bd for a time zone in which the power load 213 operates relatively frequently and a predetermined frequency F4bn for a time zone in which the power load 213 does not operate very frequently are used. Each is stored in the setting means 212 in advance. Here, the relationship between the predetermined frequency F4bd and the predetermined frequency F4bn is set such that the predetermined frequency F4bd is higher than the predetermined frequency F4bn. In the present embodiment, the time setting unit 211 stores a predetermined time T4b in advance.

  Similarly to the case of the first embodiment, when the time zone setting means 208 determines that it is a daytime time zone based on the current time, the predetermined frequency F4bd is also set, and the time zone is a night time zone. If it is determined, the frequency setting unit 212 sets a predetermined frequency F4bn for the operation stop determination unit 209. At this time, in any case, the power threshold setting means 210 and the time setting means 211 set the operation stop power threshold W4b and the predetermined time T4b to the operation stop determination means 209. And as shown in the 3rd time slot | zone 301c of FIG. 4, even when the power consumption of the electric power load 213 is less than the shutdown electric power threshold value W4b, the frequency of the decrease is less than the predetermined frequency F4bd within the predetermined time T4b. In this case, the power generation operation of the fuel cell 202 is not stopped. In this case, the operation of the fuel processor 201 for generating the fuel gas is not stopped. At this time, the power generation operation of the fuel cell 202 is stopped when the frequency of lowering the operation stop power threshold W4b is equal to or higher than the predetermined frequency F4bd within the predetermined time T4b. In this case, the operation for generating the fuel gas of the fuel processor 201 is also stopped. More specifically, for example, when F4bd = 98%, even when power consumption exceeding the shutdown power threshold W4b occurs instantaneously as in the power consumption 341f in the third time zone 301c, the shutdown power When the load power detection means 205 detects that the threshold W4b falls below 98% within the predetermined time T4b (that is, when the frequency of the power consumption 341f within the predetermined time T4b is less than 2%). The power generation operation of the fuel cell 202 is stopped. If the power generation operation of the fuel cell 202 is not stopped, the fuel cell 202 continues to output power at the minimum output power W4d as shown in the third time zone 301c of FIG. In the third time zone 301c, the minimum output power W4d exceeds the power consumption of the power load 213. However, the excessive output generated when the fuel cell 202 continues to output power with the minimum output power W4d. Electric power is stored by a storage battery or the like as in the first embodiment.

  Also, as shown in the fourth time zone 301d, when the load power detection means 205 of the fuel cell power generation system 200 detects that the power consumption of the power load 213 has risen again, the fuel cell 202 has a power as indicated by a curve 342. Resumes output. In this case, as in the case of the second time zone 301b, as shown in the fourth time zone 301d, the power amount changing unit 207 is responsive to fluctuations in the power consumption of the power load 213 detected by the load power detecting unit 205. The output power of the fuel cell 202 is controlled between the maximum output power W4c and the minimum output power W4d so as to follow. At this time, when the power consumption of the power load 213 exceeds the output power of the fuel cell 202, the power shortage from the commercial power 214 is supplemented.

  On the other hand, as shown in the fifth time zone 301e, the load power detection means 205 detects that the power consumption of the power load 213 has fallen below the shutdown power threshold W4b by a predetermined frequency F4bn within a predetermined time T4b. In this case, the power generation operation of the fuel cell 202 is stopped by the operation stop determination unit 209. At this time, the operation of the fuel processor 201 is also stopped. More specifically, for example, when F4bn = 70%, even if power consumption exceeding the shutdown power threshold W4b occurs instantaneously like the power consumption 341g in the fifth time zone 301e, the shutdown power When the load power detection means 205 detects that the threshold W4b falls below 70% or more within the predetermined time T4b (that is, when the frequency of the power consumption 341g within the predetermined time T4b is less than 30%). The power generation operation of the fuel cell 202 is stopped. At this time, power is supplied to the power load 213 by supplying power from the commercial power 214.

  Thus, in the present embodiment, even when the power consumption of the power load 213 shifts from a high state such as the second time zone 301b to a low state such as the third time zone 301c, the operation is stopped. When power consumption equal to or lower than the power threshold W4b does not occur more than a predetermined frequency F4bd within a predetermined time T4b, the power generation operation of the fuel cell 202 is not stopped. On the other hand, when the power consumption of the power load 213 shifts from a high state such as the fourth time zone 301d to a low state such as the fifth time zone 301e, the power consumption below the shutdown power threshold W4b is predetermined. If the frequency F4bn or more occurs within the time T4b, the power generation operation of the fuel cell 202 is stopped.

  Even with such a configuration, unnecessary stop of the power generation operation of the fuel cell 202 can be prevented, so that the same effect as in the case of the first embodiment can be obtained.

  In the present embodiment, the predetermined frequency F4bd and the predetermined frequency F4bn may be set independently by the user (or the driver or the administrator) of the fuel cell power generation system 200, or in units of one week ( Alternatively, the learning unit 215 may store and learn the power consumption pattern of the power load 213 in units of one month or season), and may be set in the frequency setting unit 212. Other points are the same as those in the first embodiment.

  As described above, in the first to fourth embodiments of the present invention, the embodiment in which the power generation operation of the fuel cell is stopped based on the power consumption of the power load detected by the load power detection unit has been described. Here, regarding the determination of stoppage of the power generation operation of the fuel cell, the mode in which the power threshold condition, the time condition, and the frequency condition are each independently changed in accordance with the usage status of the fuel cell power generation system has been described in detail. However, in determining whether to stop the power generation operation of the fuel cell, even if two or more of the power threshold condition, time condition, and frequency condition are changed at the same time according to the usage status of the fuel cell power generation system, the operation is unnecessary. It is possible to reduce the number of times of stopping and continue good power generation operation in which the number of useless energy consumptions related to the start of the fuel cell is reduced. The reason for this is that by changing two or more of the power threshold condition, time condition, and frequency condition used to stop the power generation operation of the fuel cell at the same time according to the usage status of the fuel cell power generation system, This is because the conditions for stopping the power generation operation of the battery are synergistically limited, and as a result, the number of times the power generation operation of the fuel cell is stopped unnecessarily can be drastically reduced.

  Note that the control unit included in the fuel cell power generation system of the present invention is not limited to a form constituted by a pure computing unit such as a CPU, but may be a form including firmware, OS, and its peripheral devices. Further, the configuration of the present invention may be realized by software or hardware.

  Moreover, in Embodiment 1-4 of this invention, the fuel cell power generation system was mentioned as an example and demonstrated as an electric power generating apparatus. However, the present invention can be applied to any power generation device other than a fuel cell power generation system such as an engine power generation system, and the same effects as those of the embodiment of the present invention can be obtained.

  As described above, according to the fuel cell power generation system and the operation method thereof according to the present invention, an unnecessary stop of the power generation operation is prevented by changing the condition of the operation stop determination of the power generation unit according to the human activity cycle, etc. It is possible to provide a power generation apparatus with excellent energy use efficiency that can suppress wasteful energy consumption and an operation method thereof.

  From the foregoing description, many modifications and other embodiments of the present invention are obvious to one skilled in the art. Accordingly, the foregoing description should be construed as illustrative only and is provided for the purpose of teaching those skilled in the art the best mode of carrying out the invention. The details of the structure and / or function may be substantially changed without departing from the spirit of the invention.

  The power generation device and the operation method thereof according to the present invention prevent unnecessary power generation operation from being stopped by changing the conditions for determining the operation stop of the power generation unit according to the human activity cycle, etc., thereby reducing unnecessary energy consumption. It is useful as a power generation device with excellent energy utilization efficiency that can be suppressed and its operation method.

FIG. 1 is a pattern diagram schematically showing an operation pattern example of the fuel cell power generation system according to Embodiment 1 of the present invention. FIG. 2 is a pattern diagram schematically showing an operation pattern example of the fuel cell power generation system according to Embodiment 2 of the present invention. FIG. 3 is a pattern diagram schematically showing an operation pattern example of the fuel cell power generation system according to Embodiment 3 of the present invention. FIG. 4 is a pattern diagram schematically showing an operation pattern example of the fuel cell power generation system according to Embodiment 4 of the present invention. FIG. 5 is a block diagram schematically showing the configuration of the fuel cell power generation system according to Embodiments 1 to 4 of the present invention. FIG. 6 is a block diagram schematically showing a configuration of a conventional fuel cell power generation system. FIG. 7 is a pattern diagram schematically showing an operation pattern example of a conventional fuel cell power generation system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Fuel cell power generation system 100a Fuel cell 100b Output control means 100c Load electric power detection means 100d Storage battery 100e Electric power load 100f Commercial electric power 101a 1st time slot | zone 101b 2nd time slot | zone 101c 3rd time slot | zone 101d 4th time slot | zone 101e Fifth time zone 111 to 112 Curve 200 Fuel cell power generation system 201 Fuel processor 202 Fuel cell 203 Air blower 204 Inverter 205 Load power detection means 206 Control unit 207 Electric energy change means 208 Time zone setting means 209 Operation stop determination means 210 Power threshold setting means 211 Time setting means 212 Frequency setting means 213 Power load 214 Commercial power 215 Learning means 220 Condition setting means 301a First time zone 301b Second time zone 301c Third time zone 301d First 4 time zone 301e 5th time zone 311-312 curve 321-322 curve 321f, 321g power consumption 331-332 curve 341-342 curve 341f, 341g power consumption Ts operation preparation period T1a-T4a predetermined time T1b-T2b, T4b Predetermined time T3bd Predetermined time T3bn Predetermined time W1a to W4a Operation start power threshold W1b, W3b to W4b Operation stop power threshold W1bd to W2bd Operation stop power threshold W1bn to W2bn Operation stop power threshold W1c to W1d Maximum output power W4d Minimum output power

Claims (7)

Based on a power generation unit that is a fuel cell, load power detection means for detecting load power supplied to a load from a power source including the power generation unit, and the load power detected by the load power detection means and the stop condition A power generation device including an operation stop determination unit for stopping the power generation operation of the power generation unit, and a stop condition setting unit for setting the stop condition,
The operation stop determination means is
(I) When the time during which the load power detected by the load power detection means is below the instantaneous power threshold continues for a predetermined time or longer, the power generation operation of the power generation unit is stopped.
(Ii) When the integrated power amount of the load power detected by the load power detection means at a predetermined time is below an integrated power threshold, stop the power generation operation of the power generation unit, or
(Iii) When the frequency at which the load power detected by the load power detection means at a predetermined time falls below an instantaneous power threshold is equal to or higher than a predetermined frequency, the power generation operation of the power generation unit is stopped,
The stop condition setting means includes
(Iv) A setting in which the instantaneous power threshold value or the integrated power threshold value is smaller in a time zone in which the average value of the load power is larger than a plurality of time zones,
(V) a setting in which the predetermined time is longer in a time zone in which the average value of the load power is larger than a plurality of time zones; and
(Vi) a setting in which the predetermined frequency is larger in a time zone in which the average value of the load power is larger than a plurality of time zones;
A power generator that sets at least one of the above.   The power generator according to claim 1, wherein the time zone is two time zones obtained by dividing a day into a time zone including at least 2 o'clock and a time zone including at least 14:00.   2. The time zone according to claim 1, wherein the time zone is three time zones obtained by dividing one day of a time zone including at least 2 o'clock, a time zone including at least 10 o'clock and a time zone including at least 18:00 into three. Power generation device.   The time zone is divided into four times of one day of a time zone including at least 2 o'clock, a time zone including at least 8 o'clock, a time zone including at least 14 o'clock and a time zone including at least 20 o'clock. The power generation device according to claim 1, wherein   The power generator according to claim 1, wherein the time period and the stop condition are set in advance. Learning means for learning at least the time zone and the stop condition based on accumulation of data of the load power detected by the load power detection means;
The power generator according to claim 1, wherein the stop condition setting means sets the time zone and the stop condition obtained by the learning. An operation method of a power generator comprising: a power generation unit that is a fuel cell; and a load power detection unit that detects load power supplied to a load from a power source including the power generation unit,
(I) a setting in which the instantaneous power threshold value or the integrated power threshold value is smaller in a time zone in which the average value of the load power is larger than a plurality of time zones;
(Ii) a setting in which a predetermined time is longer in a time zone in which the average value of the load power is larger than a plurality of time zones; and
(Iii) a setting in which a predetermined frequency is larger in a time zone in which the average value of the load power is larger than a plurality of time zones;
At least one of
Based on the above settings,
(Iv) When the time during which the load power detected by the load power detection means is below the instantaneous power threshold continues for the predetermined time or longer, the power generation operation of the power generation unit is stopped.
(V) when the integrated power amount of the load power detected by the load power detection means at the predetermined time is below the integrated power threshold, or stop the power generation operation of the power generation unit, or
(Vi) A power generation device that stops the power generation operation of the power generation unit when the frequency at which the load power detected by the load power detection means at the predetermined time falls below the instantaneous power threshold is equal to or greater than the predetermined frequency. Driving method.

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